Jan,
I can't thank you enough for your help. Okay; so I will basically use the circular needle as if it were one really long straight needle--work off of the left onto the right, then turn the work around and go the other way? Have I got that right?

If I want to use a light baby yarn, in order to do double do I just get two skeins and pull from them both (working them together as if they were one) at the same time, or is there a better way to make a doubled strand? On the other hand, maybe I should just get a thicker/fuzzier yarn so I don't have to worry about that.